Datasheet

Reserved Characters in XML

Escape characters are characters preventing execution in a programming language or parser. Thus the <

and > characters must be escaped (using an escape sequence) if they are used in an XML document any-

where other than delimiting tags (elements). In XML, an escape sequence is a sequence of characters

known to the XML parser to represent special characters. This escape sequence is exactly the same as

that used by HTML. The following XML code is invalid:

The preceding code can be resolved into XML by replacing the < character with the escape sequence

string

< as follows:

The <, >, and & characters are illegal in XML and will be interpreted. Quotation characters of all forms

are best avoided and best replaced with an escape sequence.

Ignoring the XML Parser with CDATA

There is a special section in an XML document called the CDATA section. The XML parser ignores any-

thing within the

CDATA section. So no errors or syntax checking will be performed in the CDATA section.

The

CDATA section can be used to include scripts written in other languages such as JavaScript. The

CDATA section is the equivalent of a <SCRIPT> . . . </SCRIPT> tag enclosed section in an HTML page.

The

CDATA section begins and ends with the strings, as highlighted in the following script example:

<![CDATA[

function F_To_C

{

return ((F – 32) * (5 / 9))

}

]]>

</SCRIPT>

What Are XML Namespaces?

Two different XML documents containing elements with the same name, where those names have differ-

ent meanings, could cause conflict. This XML document contains weather forecasts for three different

cities. The

<name> element represents the name of each city:

<?xml version=”1.0”?>

<city>

<name>Frankfurt</name>

</city>

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